It has been over fifty years since the structural glass block and glass bricks became popular as an architectural feature in residences and commercial and industrial structures.
The glass blocks characteristically have an ornamented interior wall to each face. The ornamentation typically is in the form of ribs, or grids, or other ornamental designs. These provide an attractive appearance, particularly with sunlight streaming through the double layer of patterns. They also provide sufficient distortion so that the blocks may be used to provide a degree of privacy, for example, for bathroom wall use.
The edges of the faces of the glass blocks typically have a partial, circular, cross section extending slightly above the surface of the rest of the wall to provide some light diffusion across the face of the wall. The actual edge of the block or brick is usually recessed slightly and sandblasted or otherwise roughened to provide a good bonding surface for conventional masonry mortar.
The glass block is hollow, as mentioned above, and in the process of manufacture is sealed with a moisture-free, atmosphere-free, sealed interior. The many year development of glass blocks and bricks has produced a myriad of styles from the simple unornamented, nearly undistorted, transmission versions to complex designs. Despite the variety of blocks and bricks available, the costs remain measured in just a few dollars each.
For years, I have designed exterior architectural lighting fixtures and have faced and solved the problems in each fixture of designing an effective housing, lamp socket and mount, and lens assembly, as well as meeting any other requirements. The sealing of the fixture from moisture entrance has often been the most difficult problem, while allowing for easy relamping or other servicing of the fixture.
It appeared to me that the variety of standard glass blocks or bricks as they stand provide:
a) a sealed rugged lens;
b) internal patterns for light dispersion over two generally semi hemispherical patterns;
c) come in a wide variety of patterns and some colors;
d) include a built in diffuser and ideal surfaces as internal reflector.
Given these inherent features of glass blocks and bricks, I have invented a number of embodiments of novel lighting fixtures which employ glass blocks in combination with housings, lamp sockets and mounts, that produce remarkable lighting features, particularly valuable for walkway lighting.
In a first embodiment, a generally rectangular cross section bollard or post has a depth corresponding to the thickness of a glass block to be used as the lens of a walkway light. The bollard includes a hollow interior, at least in the region intended for light emission. A glass block is mounted within the bollard with its faces exposed on opposite sides of the bollard. A light source is located within the bollard exposed to one sidewall of the glass block. A socket and suitable cabling are also located in the bollard for mounting and powering the light source.
The normal sandblasted surface of each edge of the glass block, other than the edge surface directly exposed to the light source, is preferably painted or otherwise coated with a reflective coating, such as white paint, to provide a surface for reflecting any light energy reaching that side wall. Multiple reflections within the glass block produce a relatively uniform pattern and intensity of the light emitted from the two faces of the glass block whenever the light source is illuminated.
Each face of the glass block naturally produces a generally hemispherical pattern in the case of a square block and semi ellipsoidal or generally a semi egg-shaped pattern in the case of a rectangular glass block.
Various patterns are available for desired decorative effect.